The present invention relates to a wrapper for use in smoking articles as well as to smoking articles employing such wrapper. More specifically, the invention relates to an improved wrapper for a smoking article having a combustible fuel element and a physically separate aerosol generating means, the wrapper encircling at least a portion of the fuel element and comprising a permeable layer of sheet material which, during burning of the fuel element, provides a coherent layer to assist in controlling the amount of peripheral air to the burning fuel element.
Cigarette-like smoking articles have been proposed for many years. See for example, U.S. Pat. No. 2,907,686 to Siegel; U.S. Pat. Nos. 3,258,015 and 3,356,094 to Ellis et al.; U.S. Pat. No. 3,516,417 to Moses; U.S. Pat. Nos. 3,943,941 and 4,044,777 to Boyd et al.; U.S. Pat. No. 4,286,604 to Ehretsmann et al.; U.S. Pat. No. 4,326,544 to Hardwick et al.; U.S. Pat. No. 4,340,072 to Bolt et al.; U.S. Pat. No. 4,391,285 to Burnett; U.S. Pat. No. 4,474,191 to Steiner; and European patent application No. 117,355 (Hearn).
As far as the present inventors are aware, none of the foregoing smoking articles has ever realized any commercial success and none have ever been widely marketed. The absence of such smoking articles from the marketplace is believed to be due to a variety of reasons, including insufficient aerosol generation, both initially and over the life of the product, poor taste, off-taste due to thermal degradation of the smoke former and/or flavor agents, the presence of substantial pyrolysis products and sidestream smoke, and unsightly appearance.
Thus, despite decades of interest and effort, there is still no smoking article on the market which provides the benefits and advantages associated with conventional cigarette smoking, without delivering considerable quantities of incomplete combustion and pyrolysis products.
In 1985, a series of foreign patents was granted or registered disclosing novel smoking articles capable of providing the benefits and advantages associated with conventional cigarette smoking, without delivering appreciable quantities of incomplete combustion or pyrolysis products. The earliest of these patents was Liberian Patent No. 13985/3890, issued Sept. 13, 1985. This patent corresponds to a later published European patent application, Publication No. 174,645, published Mar. 19, 1986.